Quantifying structural distortion manipulation for desired perovskite phase: Part II. Three-step workflow to reveal phase evolution logic

Distortion manipulation emerges as an efficient approach to obtain desired perovskite phases for various applications. In part I of this study, we propose a paradigm to quantify the structural distortion manipulation, which enables us to obtain desired perovskite phases by translating relevant materials research into a single mathematical question. As part II of this continuous study, we construct normalized structures by introducing all possible couplings of dominant distortions into a cubic supercell and then compare them with variously shaped primitive/conventional cells known in the database. The structure comparison demonstrates that distortions are the only cause for phase and property variations. This confirms that our proposed distortion parameters can be directly used to construct phases, providing theoretical support for the paradigm in Part I. Given the limited number of distortion types, we identify that the positional relations involved in distortion arrangements and couplings are the keys to describe numerous phases. Furtherly, a three-step workflow is proposed with core contents related to the positional relation, distortion hierarchy, and distortion-component-generation ordering in spatial dimension, respectively. The definition basis and value changes of distortion/model parameters in this workflow illustration provide guidelines about how to reveal the logic behind the perovskite phase evolution.